I'm using a 12V 500mA AC-DC wall wart to power my spare car radio in the garage. The radio is getting continuous humming noise from this input. Moving the cable around wouldn't help. The radio doesn't hum when I hook it up to my regulated benchtop power supply but it has noisy cooling fans.
Is there a simple way like rigging up some kind of a capacitance filter on the wall wart DC input line to stop the noise? How should I go about it? Please suggest components together with their values. Thanks!
Is there a simple way like rigging up some kind of a capacitance filter on the wall wart DC input line to stop the noise? How should I go about it? Please suggest components together with their values. Thanks!